class Graph {

  constructor() {

    this.vertices = [];

    this.adjacencyList = {};

  }

 

  addVertex(vertex) {

    this.vertices.push(vertex);

    this.adjacencyList[vertex] = [];

  }

 

  addEdge(vertex1, vertex2) {

    this.adjacencyList[vertex1].push(vertex2);

    this.adjacencyList[vertex2].push(vertex1);

  }

 

  dfs(startVertex) {

    const visited = {};

    for (let i = 0; i < this.vertices.length; i++) {

      visited[this.vertices[i]] = false;

    }

    this._dfsHelper(startVertex, visited);

  }

 

  _dfsHelper(vertex, visited) {

    visited[vertex] = true;

    console.log(vertex);

    const neighbors = this.adjacencyList[vertex];

    for (let i = 0; i < neighbors.length; i++) {

      const neighbor = neighbors[i];

      if (!visited[neighbor]) {

        this._dfsHelper(neighbor, visited);

      }

    }

  }

 

  bfs(startVertex) {

    const visited = {};

    const queue = [];

    for (let i = 0; i < this.vertices.length; i++) {

      visited[this.vertices[i]] = false;

    }

    visited[startVertex] = true;

    queue.push(startVertex);

 

    while (queue.length > 0) {

      const vertex = queue.shift();

      console.log(vertex);

      const neighbors = this.adjacencyList[vertex];

      for (let i = 0; i < neighbors.length; i++) {

        const neighbor = neighbors[i];

        if (!visited[neighbor]) {

          visited[neighbor] = true;

          queue.push(neighbor);

        }

      }

    }

  }

}

 

// Example usage:

const graph = new Graph();

graph.addVertex('A');

graph.addVertex('B');

graph.addVertex('C');

graph.addVertex('D');

graph.addEdge('A', 'B');

graph.addEdge('A', 'C');

graph.addEdge('B', 'D');

graph.addEdge('C', 'D');

 

console.log('Depth First Search:');

graph.dfs('A');

console.log('Breadth First Search:');

graph.bfs('A');

Output:-

Depth First Search:

A

B

D

C

Breadth First Search:

A

B

C

D